private Album addAlbum(String title, Artist albumArtist) {
Album album = null;
// special case treatments
if (this.isSpecialCase(albumArtist)){
if (albumArtist instanceof VariousArtists){
album = new VariousArtistsAlbum(title, albumArtist, source);
}
} else {
album = new AlbumImpl(title, albumArtist, source);
}